add comments for cpm

Author: jason1028kr

pkg/custompluginmonitor/custom_plugin_monitor.go

@@ -120,6 +120,8 @@ func (c *customPluginMonitor) Stop() {
 }
 
 // monitorLoop is the main loop of customPluginMonitor.
+// there is one customPluginMonitor, one plugin instance for each configPath.
+// each runs rules in parallel at pre-configured concurrency, and interval.
 func (c *customPluginMonitor) monitorLoop() {
 	if !*c.config.PluginGlobalConfig.SkipInitialStatus {
 		c.initializeStatus()

pkg/custompluginmonitor/plugin/plugin.go

@@ -93,6 +93,7 @@ func (p *Plugin) runRules() {
 	glog.V(3).Info("Start to run custom plugins")
 
 	for _, rule := range p.config.Rules {
+		// syncChan limits concurrent goroutines to configured PluginGlobalConfig.Concurrency value
 		p.syncChan <- struct{}{}
 		p.Add(1)
 		go func(rule *cpmtypes.CustomRule) {
@@ -116,6 +117,7 @@ func (p *Plugin) runRules() {
 				Message:    message,
 			}
 
+			// pipes result into resultChan which customPluginMonitor instance generates status from
 			p.resultChan <- result
 
 			// Let the result be logged at a higher verbosity level. If there is a change in status it is logged later.